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Putting Research into Use (RIU): Technology Development for the Poor Farmer in Low Income countries
The Research Into Use programme aims to help agricultural research projects put its existing stock of knowledge into practical use rather than investing in new scientific research. In doing this, it hopes to increase the reach of the scientific projects in low-income countries and set up productive, sustainable and high impact technologic development projects
ASPIRE Aerodynamic Models and Flight Performance
The Advanced Supersonic Parachute Inflation Research Experiments (ASPIRE) project waslaunched to develop the capability for testing supersonic parachutes at Mars-relevant conditions.Three initial parachute tests, targeted as a risk-reduction activity for NASA's upcomingMars2020 mission, successfully tested two candidate parachute designs and provided valuabledata on parachute inflation, forces, and aerodynamic behavior. Design of the flight tests dependedon flight mechanics simulations which in turn required aerodynamic models for the payload, andthe parachute. Computational Fluid Dynamics (CFD) was used to generate these models preflightand are compared against the flight data after the tests. For the payload, the reconstructedaerodynamic behavior is close to the pre-flight predictions, but the uncertainties in thereconstructed data are high due to the low dynamic pressures and accelerations during the flightperiod of comparison. For the parachute, the predicted time to inflation agrees well with the preflightmodel; the peak aerodynamic force and the steady state drag on the parachute are withinthe bounds of the pre-flight models, even as the models over-predict the parachute drag atsupersonic Mach numbers. Notably, the flight data does not show the transonic drag decreasepredicted by the pre-flight model. The ASPIRE flight tests provide previously unavailablevaluable data on the performance of a large full-scale parachute behind a slender leading bodyat Mars-relevant Mach number, dynamic pressure and parachute loads. This data is used topropose a new model for the parachute drag behind slender bodies to aid future experiments
Double-beta decay Q values of 130Te, 128Te, and 120Te
The double-beta decay Q values of 130Te, 128Te, and 120Te have been
determined from parent-daughter mass differences measured with the Canadian
Penning Trap mass spectrometer. The 132Xe-129Xe mass difference, which is
precisely known, was also determined to confirm the accuracy of these results.
The 130Te Q value was found to be 2527.01(32) keV which is 3.3 keV lower than
the 2003 Atomic Mass Evaluation recommended value, but in agreement with the
most precise previous measurement. The uncertainty has been reduced by a factor
of 6 and is now significantly smaller than the resolution achieved or foreseen
in experimental searches for neutrinoless double-beta decay. The 128Te and
120Te Q values were found to be 865.87(131) keV and 1714.81(125) keV,
respectively. For 120Te, this reduction in uncertainty of nearly a factor of 8
opens up the possibility of using this isotope for sensitive searches for
neutrinoless double-electron capture and electron capture with positron
emission.Comment: 5 pages, 2 figures, submitted to Physical Review Letter
Non-BCS pairing in anisotropic strongly correlated electron systems in solids
The problem of pairing in anisotropic electron systems possessing patches of
fermion condensate in the vicinity of the van Hove points is analyzed.
Attention is directed to opportunities for the occurrence of non-BCS pairing
correlations between the states belonging to the fermion condensate. It is
shown that the physical emergence of such pairing correlations would
drastically alter the behavior of the single-particle Green function, the
canonical pole of Fermi-liquid theory being replaced by a branch point.Comment: 7 page
Extra-planar gas in the spiral galaxy NGC 4559
We present 21-cm line observations of the spiral galaxy NGC 4559, made with
the Westerbork Synthesis Radio Telescope. We have used them to study the HI
distribution and kinematics, the relative amount and distribution of luminous
and dark matter in this galaxy and, in particular, the presence of extra-planar
gas. Our data do reveal the presence of such a component, in the form of a
thick disk, with a mass of 5.9 x 10^8 Mo (one tenth of the total HI mass) and a
mean rotation velocity 25-50 km/s lower than that of the thin disk. The
extra-planar gas may be the result of galactic fountains but accretion from the
IGM cannot be ruled out. With this study we confirm that lagging, thick HI
layers are likely to be common in spiral galaxies.Comment: 17 pages, 10 figures. Accepted for publication in A&
17 ways to say yes:Toward nuanced tone of voice in AAC and speech technology
People with complex communication needs who use speech-generating devices have very little expressive control over their tone of voice. Despite its importance in human interaction, the issue of tone of voice remains all but absent from AAC research and development however. In this paper, we describe three interdisciplinary projects, past, present and future: The critical design collection Six Speaking Chairs has provoked deeper discussion and inspired a social model of tone of voice; the speculative concept Speech Hedge illustrates challenges and opportunities in designing more expressive user interfaces; the pilot project Tonetable could enable participatory research and seed a research network around tone of voice. We speculate that more radical interactions might expand frontiers of AAC and disrupt speech technology as a whole
Beta-delayed-neutron studies of Sb and I performed with trapped ions
Beta-delayed-neutron (n) spectroscopy was performed using the
Beta-decay Paul Trap and an array of radiation detectors. The n
branching ratios and energy spectra for Sb and I were
obtained by measuring the time of flight of recoil ions emerging from the
trapped ion cloud. These nuclei are located at the edge of an isotopic region
identified as having n branching ratios that impact the r-process
abundance pattern around the A~130 peak. For Sb and I,
n branching ratios of 14.6(11)%, 17.6(28)%, and 7.6(28)% were
determined, respectively. The n energy spectra obtained for Sb
and I are compared with results from direct neutron measurements, and
the n energy spectrum for Sb has been measured for the first
time
Designing electronic collaborative learning environments
Electronic collaborative learning environments for learning and working are in vogue. Designers design them according to their own constructivist interpretations of what collaborative learning is and what it should achieve. Educators employ them with different educational approaches and in diverse situations to achieve different ends. Students use them, sometimes very enthusiastically, but often in a perfunctory way. Finally, researchers study them and—as is usually the case when apples and oranges are compared—find no conclusive evidence as to whether or not they work, where they do or do not work, when they do or do not work and, most importantly, why, they do or do not work. This contribution presents an affordance framework for such collaborative learning environments; an interaction design procedure for designing, developing, and implementing them; and an educational affordance approach to the use of tasks in those environments. It also presents the results of three projects dealing with these three issues
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